Beneficial Effect of a Multistrain Synbiotic Prodefen® Plus on the Systemic and Vascular Alterations Associated with Metabolic Syndrome in Rats: The Role of the Neuronal Nitric Oxide Synthase and Protein Kinase A.

A high fat diet (HFD) intake is crucial for the development and progression of metabolic syndrome (MtS). Increasing evidence links gut dysbiosis with the metabolic and vascular alterations associated with MtS. Here we studied the use of a combination of various probiotic strains together with a prebiotic (synbiotic) in a commercially available Prodefen® Plus. MtS was induced by HFD (45%) in male Wistar rats. Half of the MtS animals received Prodefen® Plus for 4 weeks. At 12 weeks, we observed an increase in body weight, together with the presence of insulin resistance, liver steatosis, hypertriglyceridemia and hypertension in MtS rats. Prodefen® Plus supplementation did not affect the body weight gain but ameliorated all the MtS-related symptoms. Moreover, the hypertension induced by HFD is caused by a diminished both nitric oxide (NO) functional role and release probably due to a diminished neuronal nitric oxide synthase (nNOS) activation by protein kinase A (PKA) pathway. Prodefen® Plus supplementation for 4 weeks recovered the NO function and release and the systolic blood pressure was returned to normotensive values as a result. Overall, supplementation with Prodefen® Plus could be considered an interesting non-pharmacological approach in MtS.

Molecular pathways involved in the cardioprotective effects of intravenous statin administration during ischemia.

The success of therapies targeting myocardial reperfusion injury is limited, while the cardioprotective impact of mitigating ischemia-related damage remains less explored. We have recently shown in a pig model that the intravenous administration of a modified atorvastatin preparation during ischemia attenuates the rise of cardiac ischemia injury biomarkers. In the following study, we sought to investigate the mechanisms behind these ischemia-related cardioprotective effects. Ischemia was induced by 90 min total coronary balloon occlusion in pigs fed a normocholesterolemic regime. Fifteen minutes after the onset of ischemia, animals were randomized to receive intravenous atorvastatin preparation (IV-atorva) or vehicle. After ischemia animals were euthanized to assess the effect of IV-atorva treatment on gene and protein levels/activation of senescence-, apoptosis-, and cardioprotective/metabolic-related markers. Proof-of-concept studies were carried out in mice and rats in which treatments or vehicle were administered 15 min after initiation of ischemia induced by permanent coronary ligation. Western-blot analyses revealed that in the ischemic myocardium of IV-atorva-treated pigs, RhoA was inactivated, phosphorylation of p53 and caspase-3 was reduced and AMPK was activated with the consequent regulation of the mTOR/raptor-signaling pathway. IV-atorva-treated rats showed, as compared to vehicle, a significant reduction (60%) in scar size assessed at 1 month by histological staining, and mice studies demonstrated the causal involvement of AMPK activation in IV-atorva mediated cardioprotective effects. We demonstrate in pigs and rodents that prompt intravenous treatment with atorvastatin during ischemia limits cardiac cell death and reduces infarct size through AMPK signaling.

Silybum marianum provides cardioprotection and limits adverse remodeling post-myocardial infarction by mitigating oxidative stress and reactive fibrosis.

AIMS: Milk thistle (Silybum marianum; SM) is an herb commonly used for hepatoprotection with antioxidant and antifibrotic properties. We investigated in pigs the cardiac effects of SM intake during the acute phase of myocardial infarction (MI) and remodeling period post-MI. METHODS: Study-1 tested the effect of SM use on the acute phase of MI. Hence, animals were distributed to a control group or to receive SM prior infarction (1.5 h ischemia). Animals were sacrificed after 2.5 h of reperfusion. Study-2 tested the effect of SM use in the cardiac remodeling phase. Accordingly, animals received for 10 d diet ±â€¯SM prior MI and followed the same regime for 3 weeks and then sacrificed. Study-3 tested the effect of SM in a non-infarcted heart; therefore, animals received for 10 d diet ±â€¯SM and then sacrificed. RESULTS: Animals taking SM before MI showed a reduction in cardiac damage (decreased oxidative damage, ROS production and xanthine oxidase levels; preserved mitochondrial function; and increased myocardial salvage; p < 0.05) versus controls. Animals that remained on chronic SM intake post-MI improved left ventricular remodeling. This was associated with the attenuation of the TGFß1/TßRs/SMAD2/3 signaling, lower myofibroblast transdifferentiation and collagen content in the border zone (p < 0.05 vs. all other groups). Cardiac contractility improved in animals taking SM (p < 0.05 vs. post-MI-control). No changes in cardiac function or fibrosis were detected in animals on SM but without MI. CONCLUSION: Intake of SM protects the heart against the deleterious effects of an MI and favors cardiac healing. These benefits may be attributed to the antioxidant and antifibrotic properties of SM.

El enriquecimiento de la dieta con polifenoles previene la disfunción endotelial coronaria mediante la activación de la vía de Akt/eNOS / Polyphenol-enriched diet prevents coronary endothelial dysfunction by activating the akt/enos pathway

Introducción y objetivos La dieta mediterránea rica en polifenoles se ha demostrado cardioprotectora, pero se desconocen los mecanismos implicados. Se ha investigado los efectos de un extracto de granada rico en polifenoles en la función coronaria de un modelo porcino. Métodos Los animales ingirieron durante 10 días una dieta normocolesterolémica o hipercolesterolémica. La mitad de los cerdos recibieron un suplemento de 625 mg/día de un extracto de granada (Pomanox®; 200 mg punicalaginas/día). Se analizó (flujo-Doppler) la vasodilatación tras la administración coronaria de acetilcolina, ionóforo de calcio, nitroprusiato de sodio y L-NG-monometilarginina (inhibidor de la enzima óxido nítrico sintasa endotelial) y la activación del eje Akt/óxido nítrico sintasa endotelial, la expresión de proteína quimiotáctica de monocitos–1 y el daño oxidativo coronario del ácido desoxirribonucleico y la oxidación de las lipoproteínas. Resultados Pomanox® redujo la disfunción endotelial inducida por la dieta hipercolesterolémica a valores de animales normocolesterolémicos tras la estimulación con acetilcolina y/o ionóforo de calcio. Este efecto se asoció con mayor actividad coronaria de Akt/óxido nítrico sintasa endotelial, menor expresión de proteína quimioatáctica de monocitos–1 y menor daño oxidativo. Las lipoproteínas de alta densidad mostraron mayor capacidad antioxidante y las lipoproteínas de baja densidad fueron más resistentes a la oxidación. Pomanox® no afectó a la vasorrelajación de los animales normocolesterolémicos. Todos los animales mostraron similar vasodilatación tras la administración de nitroprusiato de sodio y la L-NG-monometilarginina bloqueó la vasorrelajación de todos los agentes vasoactivos, a excepción del nitroprusiato de sodio. Conclusiones La toma de Pomanox® previene la disfunción endotelial coronaria inducida por la hiperlipemia, al preservar el eje Akt/óxido nítrico sintasa endotelial y contrarrestar la inflamación y el daño oxidativo vascular (AU)

Introduction and objectives: The Mediterranean diet, rich in polyphenols, has shown to be cardioprotective. However the mechanisms involved remain unknown. We investigated whether supplementation with a pomegranate extract rich in polyphenols renders beneficial effects on coronary function in a clinically relevant experimental model and characterized the underlying mechanisms. Methods: Pigs were fed a 10-day normocholesterolemic or hypercholesterolemic diet. Half of the animals were given a supplement of 625 mg/day of a pomegranate extract (PomanoxW; 200 mg punicalagins/day). Coronary responses to escalating doses of vasoactive drugs (acetylcholine, calciumionophore, and sodium nitroprusside) and L-NG-monomethylarginine (endothelial nitric oxide synthase inhibitor) were measured using flow Doppler. Akt/endothelial nitric oxide-synthase axis activation, monocyte chemoattractant protein-1 expression, oxidative deoxyribonucleic acid damage in the coronary artery, and lipoprotein resistance to oxidation were evaluated. Results: In dyslipidemic animals, PomanoxW supplementation prevented diet-induced impairment of endothelial relaxation, reaching vasodilatory values comparable to normocholesterolemic animals upon stimulation with acetylcholine and/or calcium ionophore. These beneficial effects were associated with vascular Akt/endothelial nitric oxide-synthase activation and lower monocyte chemoattractant protein-1 expression. PomanoxW supplementation reduced systemic oxidative stress (higher high-density (..) (AU)

Intake of cooked tomato sauce preserves coronary endothelial function and improves apolipoprotein A-I and apolipoprotein J protein profile in high-density lipoproteins.

Intake of tomatoes has been linked with healthy diets (eg, Mediterranean diet). However, it remains unknown whether tomato intake exerts protective effects on the vasculature. The aim of this study was to determine whether medium-term supplementation with cooked tomato sauce (CTS) Mediterranean style (sofrito) attenuates diet-induced coronary endothelial dysfunction in an animal model with clinical impact and explore the mechanisms behind the effects. Pigs (N = 18) were fed a 10-day hypercholesterolemic diet. Half of the animals were given a supplement of 100 g/d of CTS (21.5 mg lycopene per day). Coronary responses to escalating doses of vasoactive drugs (acetylcholine, calcium ionophore, and sodium nitroprusside) and L-NG-monomethylarginine (endothelial nitric oxide synthase [eNOS] inhibitor) were measured using flow Doppler. In the coronary arteries, we investigated eNOS gene expression and activation, monocyte chemoattractant protein 1 (MCP-1) expression, and oxidative DNA damage. In the circulation, we investigated lipoprotein resistance to oxidation and the differential proteomic protein profile. In dyslipidemic animals, CTS intake prevented diet-induced impairment of receptor-operated and nonreceptor-operated endothelial-dependent coronary vasodilation. These beneficial effects were associated with enhanced eNOS transcription and activation and diminished DNA damage in the coronary arteries. CTS-fed animals showed lower lipid peroxidation, higher high-density lipoprotein (HDL) antioxidant potential and plasma lycopene levels of 0.16 mg/L. Interestingly, improved HDL functionality was associated with protein profile changes in apolipoprotein A-I and apolipoprotein J. Lipids levels and MCP-1 expression were not affected by CTS. We report that CTS intake protects against low-density lipoprotein-induced coronary endothelial dysfunction by reducing oxidative damage, enhancing eNOS expression and activity, and improving HDL functionality.

Polyphenol-enriched diet prevents coronary endothelial dysfunction by activating the Akt/eNOS pathway.

INTRODUCTION AND OBJECTIVES: The Mediterranean diet, rich in polyphenols, has shown to be cardioprotective. However the mechanisms involved remain unknown. We investigated whether supplementation with a pomegranate extract rich in polyphenols renders beneficial effects on coronary function in a clinically relevant experimental model and characterized the underlying mechanisms. METHODS: Pigs were fed a 10-day normocholesterolemic or hypercholesterolemic diet. Half of the animals were given a supplement of 625 mg/day of a pomegranate extract (Pomanox; 200 mg punicalagins/day). Coronary responses to escalating doses of vasoactive drugs (acetylcholine, calcium ionophore, and sodium nitroprusside) and L-NG-monomethylarginine (endothelial nitric oxide-synthase inhibitor) were measured using flow Doppler. Akt/endothelial nitric oxide-synthase axis activation, monocyte chemoattractant protein-1 expression, oxidative deoxyribonucleic acid damage in the coronary artery, and lipoprotein resistance to oxidation were evaluated. RESULTS: In dyslipidemic animals, Pomanox supplementation prevented diet-induced impairment of endothelial relaxation, reaching vasodilatory values comparable to normocholesterolemic animals upon stimulation with acetylcholine and/or calcium ionophore. These beneficial effects were associated with vascular Akt/endothelial nitric oxide-synthase activation and lower monocyte chemoattractant protein-1 expression. Pomanox supplementation reduced systemic oxidative stress (higher high-density lipoprotein-antioxidant capacity and higher low-density lipoprotein resistance to oxidation) and coronary deoxyribonucleic acid damage. Normocholesterolemic animals elicited similar drug-related vasodilation regardless of Pomanox supplementation. All animals displayed a similar vasodilatory response to sodium nitroprusside and L-NG-monomethylarginine blunted all vasorelaxation responses except for sodium nitroprusside. CONCLUSIONS: Pomanox supplementation hinders hyperlipemia-induced coronary endothelial dysfunction by activating the Akt/endothelial nitric oxide-synthase pathway and favorably counteracting vascular inflammation and oxidative damage.

A novel anti-ischemic nitric oxide donor inhibits thrombosis without modifying haemodynamic parameters.

Platelets are involved in the clinical presentations of ischemic heart disease. Our objective was to study the antithrombotic effects of a new nitric oxide donor (LA419), a neutral sugar organic nitrate with a protected thiol group in its molecular structure. Animals were randomly distributed in three groups: I) oral administration of LA419 (0.9-1.8-3.6-5 mg/kg/d, 10 days); II) oral administration of standard IS-5-MN (0.9-1.8 mg/kg/d, 10 days); III) non-treated group (control). In catheterized pigs, thrombosis was studied under controlled rheological conditions by radioisotopic evaluation of deposited platelets on damaged vessel wall, placed in an extracorporeal perfusion chamber. Changes in blood pressure, heart rate, and platelet aggregation were evaluated. Results have shown that LA419 significantly decreased thrombus formation according to the degree of vascular damage, and shear rate conditions in a dose-dependent manner (p<0.005), without significant modifications on blood pressure and/or elevation of liver enzymes. In contrast, IS-5-MN only showed a significant reduction on platelet deposition at the high dose, that was associated to hypotension and elevation of liver enzymes. Therefore, we conclude that this new anti-ischemic NO-donor (NOd) LA419 that inhibits platelet function without modifying blood pressure may be a highly efficacious strategy to passivate platelet activation induced by a damaged vessel wall.